% APNIC found the following authoritative answer from: whois.ripe.net

% This is the RIPE Database query service.
% The objects are in RPSL format.
%
% The RIPE Database is subject to Terms and Conditions.
% See https://docs.db.ripe.net/terms-conditions.html

% Note: this output has been filtered.
%       To receive output for a database update, use the "-B" flag.

% Information related to '146.50.0.0 - 146.50.255.255'

% Abuse contact for '146.50.0.0 - 146.50.255.255' is 'abuse@uva.nl'

inetnum:        146.50.0.0 - 146.50.255.255
netname:        UVANET2
descr:          Universiteit van Amsterdam
country:        NL
org:            ORG-UVA9-RIPE
admin-c:        UVA1024-RIPE
tech-c:         UVA1024-RIPE
abuse-c:        UVA3322-RIPE
status:         LEGACY
remarks:        ----------------------------------------------------
remarks:        Regarding security incidents please contact CERT-UVA
remarks:        For information about CERT-UvA: http://uva.nl/cert
remarks:        ----------------------------------------------------
mnt-by:         RIPE-NCC-LEGACY-MNT
mnt-by:         AS1124-MNT
created:        2002-08-27T13:45:42Z
last-modified:  2023-12-20T16:43:27Z
source:         RIPE # Filtered
mnt-domains:    AS1124-MNT
sponsoring-org: ORG-Sb3-RIPE

organisation:   ORG-UVA9-RIPE
org-name:       Universiteit van Amsterdam
country:        NL
org-type:       OTHER
address:        Universiteit van Amsterdam
address:        ICT Services
address:        Hogehilweg 21
address:        NL-1101CB Amsterdam
address:        The Netherlands
admin-c:        UVA1024-RIPE
tech-c:         UVA1024-RIPE
abuse-c:        UVA3322-RIPE
mnt-ref:        AS1124-MNT
mnt-by:         AS1124-MNT
created:        2014-10-14T11:39:09Z
last-modified:  2023-12-20T14:51:09Z
source:         RIPE # Filtered

role:           UvA Hostmaster
address:        Universiteit van Amsterdam
address:        ICT Services
address:        Hogehilweg 21
address:        NL-1101CB Amsterdam
address:        The Netherlands
abuse-mailbox:  abuse@uva.nl
remarks:        ----------------------------------------------------
remarks:        Regarding security incidents please contact CERT-UvA
remarks:        For information about CERT-UvA: http://uva.nl/cert
remarks:        ----------------------------------------------------
admin-c:        JPV1024-RIPE
tech-c:         JPV1024-RIPE
tech-c:         SB1024
tech-c:         TH1024
tech-c:         JK1024
nic-hdl:        UVA1024-RIPE
mnt-by:         AS1124-MNT
created:        2009-10-08T15:52:10Z
last-modified:  2023-12-20T15:11:43Z
source:         RIPE # Filtered

% Information related to '146.50.0.0/16AS1103'

route:          146.50.0.0/16
descr:          UVANET2
origin:         AS1103
mnt-by:         AS1103-MNT
mnt-by:         AS1124-MNT
created:        2002-08-28T08:13:25Z
last-modified:  2013-03-26T15:39:23Z
source:         RIPE

% Information related to '146.50.0.0/16AS1124'

route:          146.50.0.0/16
descr:          UVANET2
origin:         AS1124
mnt-by:         AS1124-MNT
created:        2013-03-26T15:47:56Z
last-modified:  2013-03-26T15:47:56Z
source:         RIPE

% This query was served by the RIPE Database Query Service version 1.114 (ABERDEEN)

Search for
IP address lookups			Miscellaneous queries
-l	1st level less specific		-i	Inverse attributes	None admin-c admin-c,tech-c,zone-c author cross-mnt cross-nfy local-as mbrs-by-ref member-of mnt-by mnt-lower mnt-nfy mnt-routes notify nserver origin person referral-by rev-srv sub-dom tech-c upd-to zone-c
-L	All less specific		-T	Object types	All as-block as-set aut-num domain filter-set inet-rtr inet6num inetnum irt key-cert mntner peering-set person role route route-set rtr-set
-m	1st level more specific
-M	All more specific		Query hints Include "AS" in front of an AS number. Example: AS4808 Include "-t" (template only) or "-v" (template and description) in front of an object name to view the template Example: -t inetnum
-x	Exact match only
-d	Associated reverse domain